So, what happens when you consciously try to create something different? Is it utterly distasteful to you?
Sure, using motifs, if melodic you will certainly hear a lot of overly familiar intervallic relationships, and and rhythmic - we've all heard those common/'uncommon' meters plenty as well. But this doesn't mean your melody will certainly mimic something you've heard, though, it may come close to something you haven't heard.
If you're actually 'trying' not to mimic something, and create something 'new' to yourself, then I think all is well, because for you, you have innovated yourself. You have gone through the process of overcoming your current norm. That is respectable...to an extent, because, then you show someone your creation, and they point you to the mass of music that is like your new work.
Well, then, are you going to try and create something new out of this next thing, or go back to your old way, or what - maybe you should mix what you learned about your newer style, into your older - try and get the best aspects out of both worlds...or as many worlds as you like.
It is up to you to try and break from your own mould. I think it is exciting to decide where to go from here, as you keep growing, or at least changing...all along the way. As long as you're not stagnant, then your growth is a very personal one, and I think that it should be cherished, regardless if the world has already heard something like it.
It depends on you, I think.
Surely you won't sound EXACTLY like things you've already heard, if you can manage your 'personal touch'. But, then again, how literal were you in the OP?